Extinctions of North American Fishes During the past Century

Abstract At first glance, it seems appealing to suggest additional wheelsets under a given railcar type. From the track’s viewpoint, and in a simplistic analysis, trading a particular car’s four-axles for the use of six should allow half again more car weight. This paper will examine efforts to test this concept over the past century. Indeed, the railway marketplace has investigated the three-axle truck in both the freight and passenger car arenas multiple times over the past century. Except in heavy-duty flatcars, the record shows that each implementation has proven to be only temporary. In general, three-axle freight trucks were developed for use with steam locomotive tenders in the early 20th century. These designs were then adapted to other car types over several decades, involving thousands of individual cars. Today, three-axle trucks are nearly extinct. This paper will address the history and status of three-axle freight trucks (or bogies) as used in North American railcar operations. Various past 20th-century applications will be discussed. International efforts will be reviewed as well. The very limited and remaining current usage of three-axle trucks is also discussed.

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Changing archaeology's ‘brand’ would be helpful

Antiquity ◽

10.15184/aqy.2018.16 ◽

2018 ◽

Vol 92 (362) ◽

pp. 523-524 ◽

Cited By ~ 5

Author(s):

Larry J. Zimmerman

Keyword(s):

North American ◽

Past Century ◽

The Past ◽

Heritage Studies

González-Ruibal et al. raise challenging issues that seem frightening in their implications. In both their specificity and their wider theoretical contexts, I had previously given these issues little thought, and some I had not even recognised. I share fully the authors’ concern that archaeologists must seek ways to engage people influenced by ‘reactionary populism’, people who “are diverse, fragmented and complex”, and who may be “greedy, patriarchal, xenophobic or uninterested in the past” (González-Ruibal et al. above). The authors find fault with the multi-vocal, multi-cultural approaches of epistemic populist archaeologies that tend to exclude most of those who fit this description. I could object to some of the details of the authors’ critiques of epistemic populism and heritage studies, but their core arguments are mostly correct and powerful. At the same time, at least within a North American context, I think that archaeologists have generally reacted to the various populist pressures of the past century and that we have already started to do what the authors suggest.

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Minimal net incision of the northern Sierra Nevada (California, USA) since the Eocene–early Oligocene

Geology ◽

10.1130/g47902.1 ◽

2020 ◽

Vol 48 (10) ◽

pp. 1023-1027

Author(s):

Emmanuel J. Gabet ◽

Daniel P. Miggins

Keyword(s):

Sierra Nevada ◽

North American ◽

Past Century ◽

Mountain Range ◽

Late Cenozoic ◽

North American Cordillera ◽

The Past ◽

The North ◽

Early Oligocene ◽

Northern Half

Abstract Significant late Cenozoic uplift (>1000 m) of the northern half of the Sierra Nevada (California, USA), a mountain range in the North American Cordillera, has been a dominant paradigm over the past century. This paradigm has been supported by evidence suggesting that in response to this recent uplift, the range’s deep canyons were incised in the past 3–4 m.y. However, paleochannel elevations compiled from a mining report and geological maps demonstrate that while some modern rivers have incised 560 m below their Eocene–early Oligocene riverbeds, incision by others has been <300 m. For example, Eocene–early Oligocene fluvial gravels can be found just 161 m above the modern channel deep within the canyon of the South Fork American River. We conclude that the initiation of late Cenozoic incision was due to a resumption of a period of downcutting that was interrupted in the Eocene when the rivers were buried by fluvial sediment and by later volcanic deposits. This interpretation challenges the hypothesis that recent uplift was responsible for deep canyon incision. Correctly identifying the causes of recent incision in the northern Sierra Nevada has important implications for understanding the geological history of the North American Cordillera because the range is hypothesized to have been the western ramp of the Nevadaplano.

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Potential for14C Dating of Biogenic Carbonate in Hackberry (Celtis) Endocarps

Quaternary Research ◽

10.1006/qres.1997.1894 ◽

1997 ◽

Vol 47 (3) ◽

pp. 337-343 ◽

Cited By ~ 26

Author(s):

Yang Wang ◽

A.Hope Jahren ◽

Ronald Amundson

Keyword(s):

Late Pleistocene ◽

North American ◽

Mineral Content ◽

Early Holocene ◽

Archaeological Sites ◽

Past Century ◽

Quaternary Sediments ◽

Biogenic Carbonate ◽

The Past ◽

Suitable Substrate

Hackberry endocarp (Celtissp.) contains significant amounts (up to 70 wt%) of biogenic carbonate that is nearly pure aragonite (CaCO3). Because of their high mineral content, hackberry endocarps are found abundantly in Tertiary and Quaternary sediments and are very common in many North American archaeological sites. We analyzed the14C content of different components of modern hackberries including the biogenic carbonate in hackberry endocarps collected at known times over the past century. The14C content of the endocarp carbonate accurately records the14C content of the atmosphere.14C dates of fossil endocarp carbonates compared favorably with dates obtained by other means at archaeological and geological sites ranging in age from the late Pleistocene through the early Holocene. We therefore suggest that hackberry endocarp is a suitable substrate for14C dating provided that its morphological and mineralogical integrity is preserved.

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The zoonotic potential of bat-borne coronaviruses

Emerging Topics in Life Sciences ◽

10.1042/etls20200097 ◽

2020 ◽

Vol 4 (4) ◽

pp. 365-381

Author(s):

Ny Anjara Fifi Ravelomanantsoa ◽

Sarah Guth ◽

Angelo Andrianiaina ◽

Santino Andry ◽

Anecia Gentles ◽

...

Keyword(s):

Genetic Material ◽

Field Research ◽

Sympatric Species ◽

Animal Origin ◽

Mammalian Host ◽

Past Century ◽

The Past ◽

Novel Host ◽

Horseshoe Bat ◽

Human Infections

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.

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PCSK9 inhibition for LDL lowering and beyond – implications for patients with peripheral artery disease

VASA ◽

10.1024/0301-1526/a000689 ◽

2018 ◽

Vol 47 (3) ◽

pp. 165-176 ◽

Cited By ~ 4

Author(s):

Katrin Gebauer ◽

Holger Reinecke

Keyword(s):

Cardiovascular Risk ◽

Risk Reduction ◽

Ldl Receptor ◽

Density Lipoprotein ◽

Past Century ◽

Pcsk9 Inhibitors ◽

Cardiovascular Risk Reduction ◽

Simultaneous Application ◽

The Past ◽

Pcsk9 Inhibition

Abstract. Low-density lipoprotein cholesterol (LDL-C) has been proven to be a causal factor of atherosclerosis and, along with other triggers like inflammation, the most frequent reason for peripheral arterial disease. Moreover, a linear correlation between LDL-C concentration and cardiovascular outcome in high-risk patients could be established during the past century. After the development of statins, numerous randomized trials have shown the superiority for LDL-C reduction and hence the decrease in cardiovascular outcomes including mortality. Over the past decades it became evident that more intense LDL-C lowering, by either the use of highly potent statin supplements or by additional cholesterol absorption inhibitor application, accounted for an even more profound cardiovascular risk reduction. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a serin protease with effect on the LDL receptor cycle leading to its degradation and therefore preventing continuing LDL-C clearance from the blood, is the target of a newly developed monoclonal antibody facilitating astounding LDL-C reduction far below to what has been set as target level by recent ESC/EAS guidelines in management of dyslipidaemias. Large randomized outcome trials including subjects with PAD so far have been able to prove significant and even more intense cardiovascular risk reduction via further LDL-C debasement on top of high-intensity statin medication. Another approach for LDL-C reduction is a silencing interfering RNA muting the translation of PCSK9 intracellularly. Moreover, PCSK9 concentrations are elevated in cells involved in plaque composition, so the potency of intracellular PCSK9 inhibition and therefore prevention or reversal of plaques may provide this mechanism of action on PCSK9 with additional beneficial effects on cells involved in plaque formation. Thus, simultaneous application of statins and PCSK9 inhibitors promise to reduce cardiovascular event burden by both LDL-C reduction and pleiotropic effects of both agents.

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Archaeology in the Past Century

Scientific American ◽

10.1038/scientificamerican02021901-20976supp ◽

1901 ◽

Vol 51 (1309supp) ◽

pp. 20976-20977

Author(s):

W. M. Flinders Petrje

Keyword(s):

Past Century ◽

The Past

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Catholicism and Cosmopolitanism: the Confluence of Three Catholic Scholars and the Cosmopolitan Democrats on State Sovereignty and the Future of Global Governance

De Ethica A Journal of Philosophical Theological and Applied Ethics ◽

10.3384/de-ethica.2001-8819.163237 ◽

2016 ◽

Vol 3 (2) ◽

pp. 37-51

Author(s):

Matthew Bagot

Keyword(s):

Global Governance ◽

State Sovereignty ◽

Current Debate ◽

Past Century ◽

Jacques Maritain ◽

The Past ◽

Technological Advances ◽

The Future ◽

Cosmopolitan Democracy ◽

Catholic Tradition

One of the central questions in international relations today is how we should conceive of state sovereignty. The notion of sovereignty—’supreme authority within a territory’, as Daniel Philpott defines it—emerged after the Treaty of Westphalia in 1648 as a result of which the late medieval crisis of pluralism was settled. But recent changes in the international order, such as technological advances that have spurred globalization and the emerging norm of the Responsibility to Protect, have cast the notion of sovereignty into an unclear light. The purpose of this paper is to contribute to the current debate regarding sovereignty by exploring two schools of thought on the matter: first, three Catholic scholars from the past century—Luigi Sturzo, Jacques Maritain, and John Courtney Murray, S.J.—taken as representative of Catholic tradition; second, a number of contemporary political theorists of cosmopolitan democracy. The paper argues that there is a confluence between the Catholic thinkers and the cosmopolitan democrats regarding their understanding of state sovereignty and that, taken together, the two schools have much to contribute not only to our current understanding of sovereignty, but also to the future of global governance.

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Aftershocks

10.23943/princeton/9780691172330.001.0001 ◽

2017 ◽

Cited By ~ 1

Author(s):

Seva Gunitsky

Keyword(s):

Twentieth Century ◽

Regime Change ◽

International System ◽

Political Legitimacy ◽

Great Powers ◽

Past Century ◽

The Past ◽

Sudden Rise ◽

The World ◽

National Borders

Over the past century, democracy spread around the world in turbulent bursts of change, sweeping across national borders in dramatic cascades of revolution and reform. This book offers a new global-oriented explanation for this wavelike spread and retreat—not only of democracy but also of its twentieth-century rivals, fascism, and communism. The book argues that waves of regime change are driven by the aftermath of cataclysmic disruptions to the international system. These hegemonic shocks, marked by the sudden rise and fall of great powers, have been essential and often-neglected drivers of domestic transformations. Though rare and fleeting, they not only repeatedly alter the global hierarchy of powerful states but also create unique and powerful opportunities for sweeping national reforms—by triggering military impositions, swiftly changing the incentives of domestic actors, or transforming the basis of political legitimacy itself. As a result, the evolution of modern regimes cannot be fully understood without examining the consequences of clashes between great powers, which repeatedly—and often unsuccessfully—sought to cajole, inspire, and intimidate other states into joining their camps.

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Variable oil and argumentative conflict in the Middle East

Tikrit Journal For Political Science ◽

10.25130/poltic.v0i0.222 ◽

2020 ◽

pp. 824

Author(s):

Malik Daham Mata’ab

Keyword(s):

Middle East ◽

Past Century ◽

Large Area ◽

The Past ◽

The World

Oil has formed since its discovery so far one of the main causes of global conflict, has occupied this energy map a large area of conflict the world over the past century, and certainly this matter will continue for the next period in our century..

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